Contaminated sites and sediments are recognised as a large problem, constituting a danger for the environment and public health. In the contaminated areas the pollutants can damage organisms and ecosystems, and there is a risk for spreading of pollutants to adjacent areas.

The toxicity test are a very valuable complement to chemical analyses, and can be an important input for risk assessment.
Based on previous research Pelagia Miljökonsult and MCN have developed a new method using Daphnia Magna to access the toxicity of wet samples in both the dissolved and the particulate phase, i.e. two-phase daphnia test. The daphnia is a relevant water living organism which is able to digest pollutants both dissolved in water and absorbed to particle surfaces. Compared to other measurements such as chemical analysis of passive or actively sampled dissolved aquaes phase, the unique benefit of the two-phase test is its approximation of the actually bioavailable fraction.

The two phase test has since 2006 been in small-scale commercial use for assessment of contaminated sites. The wider use of the method is however still hampered by some remaining questions concerning which factors that actually cause the toxic effects on the Daphnia. The project will therefore examine factors such as the influence of non-toxic particles, and the various fractions of common pollutants such as PAHes.

The Daphnia two-phase toxicity test will furthermore be tested and validated for further applications regarding sediment and sludge(s).

The result will be published in at least one international scientific journal as well in national popular science journal.